Category: N

  • Neurotropic virus

    A virus that reproduces in nerve tissue.  

  • Nutrient vessel

    One of the vessels supplying specific areas such as the interior of bones.  

  • Noninvasive ventilation

    The use of airway support administered through a face (nasal) mask instead of an endotracheal tube. Inhaled gases are given with positive end-expiratory pressure often with pressure support or with assist control ventilation at a set tidal volume and rate. Numerous studies have shown this technique to be as effective as, and better tolerated than,…

  • Nasal valve

    The site of greatest obstruction to airflow through the nasal passages. It extends from the bony cave near the piriform aperture into part of the cartilaginous vestibule of the nose. It is also known as the “internal nasal valve.”  

  • Neurobehavioral toxicity

    Alterations in attention, concentration, coordination, mood, muscle activity, neurological development, or sensation resulting from exposure to a poisonous chemical, drug, or physical agent.  

  • Noncontact tonometry

    Determining intraocular pressure by measuring the degree of indentation of the cornea produced by a puff of air.  

  • Nonshivering thermogenesis

    A limited physiological response of the newborn infant to chilling. Hypothermia stimulates sympathetic catabolism of brown fat, which is not coupled with ATP formation, and therefore releases most energy in the form of heat. Brown fat is located mainly in the neck and chest of the infant.  

  • Normal temperature

    The temperature of the body, taken orally, in a healthy individual: normally 97.5° to 99.5°F (36° to 38°C). The normal body temperature when healthy typically ranges between 98°F and 99°F, with an average of 98.6°F.  

  • Nasal tamponade

    Compression of nasal blood vessels to stop bleeding.  

  • Narrow complex tachycardia

    Tachycardia in which the duration of the QRS complex is less than 0.12 seconds. Most narrow complex tachycardias originate from a pacemaker above the ventricles and are therefore supraventricular tachycardias.